feat(tui): file viewer, select messages

3 files changed, 228 insertions, 26 deletions

diff --git a/packages/tui/internal/layout/flex.go b/packages/tui/internal/layout/flex.go
index c7d9ee1bc..5b10a9523 100644
--- a/packages/tui/internal/layout/flex.go
+++ b/packages/tui/internal/layout/flex.go
@@ -4,7 +4,9 @@ import (
 	"strings"
 
 	"github.com/charmbracelet/lipgloss/v2"
+	"github.com/charmbracelet/lipgloss/v2/compat"
 	"github.com/sst/opencode/internal/styles"
+	"github.com/sst/opencode/internal/theme"
 )
 
 type Direction int
@@ -34,11 +36,13 @@ const (
 )
 
 type FlexOptions struct {
-	Direction Direction
-	Justify   Justify
-	Align     Align
-	Width     int
-	Height    int
+	Background *compat.AdaptiveColor
+	Direction  Direction
+	Justify    Justify
+	Align      Align
+	Width      int
+	Height     int
+	Gap        int
 }
 
 type FlexItem struct {
@@ -53,6 +57,12 @@ func Render(opts FlexOptions, items ...FlexItem) string {
 		return ""
 	}
 
+	t := theme.CurrentTheme()
+	if opts.Background == nil {
+		background := t.Background()
+		opts.Background = &background
+	}
+
 	// Calculate dimensions for each item
 	mainAxisSize := opts.Width
 	crossAxisSize := opts.Height
@@ -72,8 +82,14 @@ func Render(opts FlexOptions, items ...FlexItem) string {
 		}
 	}
 
+	// Account for gaps between items
+	totalGapSize := 0
+	if len(items) > 1 && opts.Gap > 0 {
+		totalGapSize = opts.Gap * (len(items) - 1)
+	}
+
 	// Calculate available space for grow items
-	availableSpace := max(mainAxisSize-totalFixedSize, 0)
+	availableSpace := max(mainAxisSize-totalFixedSize-totalGapSize, 0)
 
 	// Calculate size for each grow item
 	growItemSize := 0
@@ -108,6 +124,7 @@ func Render(opts FlexOptions, items ...FlexItem) string {
 			// For row direction, constrain width and handle height alignment
 			if itemSize > 0 {
 				view = styles.NewStyle().
+					Background(*opts.Background).
 					Width(itemSize).
 					Height(crossAxisSize).
 					Render(view)
@@ -116,31 +133,65 @@ func Render(opts FlexOptions, items ...FlexItem) string {
 			// Apply cross-axis alignment
 			switch opts.Align {
 			case AlignCenter:
-				view = lipgloss.PlaceVertical(crossAxisSize, lipgloss.Center, view)
+				view = lipgloss.PlaceVertical(
+					crossAxisSize,
+					lipgloss.Center,
+					view,
+					styles.WhitespaceStyle(*opts.Background),
+				)
 			case AlignEnd:
-				view = lipgloss.PlaceVertical(crossAxisSize, lipgloss.Bottom, view)
+				view = lipgloss.PlaceVertical(
+					crossAxisSize,
+					lipgloss.Bottom,
+					view,
+					styles.WhitespaceStyle(*opts.Background),
+				)
 			case AlignStart:
-				view = lipgloss.PlaceVertical(crossAxisSize, lipgloss.Top, view)
+				view = lipgloss.PlaceVertical(
+					crossAxisSize,
+					lipgloss.Top,
+					view,
+					styles.WhitespaceStyle(*opts.Background),
+				)
 			case AlignStretch:
 				// Already stretched by Height setting above
 			}
 		} else {
 			// For column direction, constrain height and handle width alignment
 			if itemSize > 0 {
-				view = styles.NewStyle().
-					Height(itemSize).
-					Width(crossAxisSize).
-					Render(view)
+				style := styles.NewStyle().
+					Background(*opts.Background).
+					Height(itemSize)
+				// Only set width for stretch alignment
+				if opts.Align == AlignStretch {
+					style = style.Width(crossAxisSize)
+				}
+				view = style.Render(view)
 			}
 
 			// Apply cross-axis alignment
 			switch opts.Align {
 			case AlignCenter:
-				view = lipgloss.PlaceHorizontal(crossAxisSize, lipgloss.Center, view)
+				view = lipgloss.PlaceHorizontal(
+					crossAxisSize,
+					lipgloss.Center,
+					view,
+					styles.WhitespaceStyle(*opts.Background),
+				)
 			case AlignEnd:
-				view = lipgloss.PlaceHorizontal(crossAxisSize, lipgloss.Right, view)
+				view = lipgloss.PlaceHorizontal(
+					crossAxisSize,
+					lipgloss.Right,
+					view,
+					styles.WhitespaceStyle(*opts.Background),
+				)
 			case AlignStart:
-				view = lipgloss.PlaceHorizontal(crossAxisSize, lipgloss.Left, view)
+				view = lipgloss.PlaceHorizontal(
+					crossAxisSize,
+					lipgloss.Left,
+					view,
+					styles.WhitespaceStyle(*opts.Background),
+				)
 			case AlignStretch:
 				// Already stretched by Width setting above
 			}
@@ -154,11 +205,14 @@ func Render(opts FlexOptions, items ...FlexItem) string {
 		}
 	}
 
-	// Calculate total actual size
+	// Calculate total actual size including gaps
 	totalActualSize := 0
 	for _, size := range actualSizes {
 		totalActualSize += size
 	}
+	if len(items) > 1 && opts.Gap > 0 {
+		totalActualSize += opts.Gap * (len(items) - 1)
+	}
 
 	// Apply justification
 	remainingSpace := max(mainAxisSize-totalActualSize, 0)
@@ -191,12 +245,17 @@ func Render(opts FlexOptions, items ...FlexItem) string {
 	// Build the final layout
 	var parts []string
 
+	spaceStyle := styles.NewStyle().Background(*opts.Background)
 	// Add space before if needed
 	if spaceBefore > 0 {
 		if opts.Direction == Row {
-			parts = append(parts, strings.Repeat(" ", spaceBefore))
+			space := strings.Repeat(" ", spaceBefore)
+			parts = append(parts, spaceStyle.Render(space))
 		} else {
-			parts = append(parts, strings.Repeat("\n", spaceBefore))
+			// For vertical layout, add empty lines as separate parts
+			for range spaceBefore {
+				parts = append(parts, "")
+			}
 		}
 	}
 
@@ -205,11 +264,19 @@ func Render(opts FlexOptions, items ...FlexItem) string {
 		parts = append(parts, view)
 
 		// Add space between items (not after the last one)
-		if i < len(sizedViews)-1 && spaceBetween > 0 {
-			if opts.Direction == Row {
-				parts = append(parts, strings.Repeat(" ", spaceBetween))
-			} else {
-				parts = append(parts, strings.Repeat("\n", spaceBetween))
+		if i < len(sizedViews)-1 {
+			// Add gap first, then any additional spacing from justification
+			totalSpacing := opts.Gap + spaceBetween
+			if totalSpacing > 0 {
+				if opts.Direction == Row {
+					space := strings.Repeat(" ", totalSpacing)
+					parts = append(parts, spaceStyle.Render(space))
+				} else {
+					// For vertical layout, add empty lines as separate parts
+					for range totalSpacing {
+						parts = append(parts, "")
+					}
+				}
 			}
 		}
 	}
@@ -217,9 +284,13 @@ func Render(opts FlexOptions, items ...FlexItem) string {
 	// Add space after if needed
 	if spaceAfter > 0 {
 		if opts.Direction == Row {
-			parts = append(parts, strings.Repeat(" ", spaceAfter))
+			space := strings.Repeat(" ", spaceAfter)
+			parts = append(parts, spaceStyle.Render(space))
 		} else {
-			parts = append(parts, strings.Repeat("\n", spaceAfter))
+			// For vertical layout, add empty lines as separate parts
+			for range spaceAfter {
+				parts = append(parts, "")
+			}
 		}
 	}
 
diff --git a/packages/tui/internal/layout/flex_example_test.go b/packages/tui/internal/layout/flex_example_test.go
new file mode 100644
index 000000000..a03346eb7
--- /dev/null
+++ b/packages/tui/internal/layout/flex_example_test.go
@@ -0,0 +1,41 @@
+package layout_test
+
+import (
+	"fmt"
+	"github.com/sst/opencode/internal/layout"
+)
+
+func ExampleRender_withGap() {
+	// Create a horizontal layout with 3px gap between items
+	result := layout.Render(
+		layout.FlexOptions{
+			Direction: layout.Row,
+			Width:     30,
+			Height:    1,
+			Gap:       3,
+		},
+		layout.FlexItem{View: "Item1"},
+		layout.FlexItem{View: "Item2"},
+		layout.FlexItem{View: "Item3"},
+	)
+	fmt.Println(result)
+	// Output: Item1   Item2   Item3
+}
+
+func ExampleRender_withGapAndJustify() {
+	// Create a horizontal layout with gap and space-between justification
+	result := layout.Render(
+		layout.FlexOptions{
+			Direction: layout.Row,
+			Width:     30,
+			Height:    1,
+			Gap:       2,
+			Justify:   layout.JustifySpaceBetween,
+		},
+		layout.FlexItem{View: "A"},
+		layout.FlexItem{View: "B"},
+		layout.FlexItem{View: "C"},
+	)
+	fmt.Println(result)
+	// Output: A             B             C
+}
diff --git a/packages/tui/internal/layout/flex_test.go b/packages/tui/internal/layout/flex_test.go
new file mode 100644
index 000000000..cad38dc8f
--- /dev/null
+++ b/packages/tui/internal/layout/flex_test.go
@@ -0,0 +1,90 @@
+package layout
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestFlexGap(t *testing.T) {
+	tests := []struct {
+		name     string
+		opts     FlexOptions
+		items    []FlexItem
+		expected string
+	}{
+		{
+			name: "Row with gap",
+			opts: FlexOptions{
+				Direction: Row,
+				Width:     20,
+				Height:    1,
+				Gap:       2,
+			},
+			items: []FlexItem{
+				{View: "A"},
+				{View: "B"},
+				{View: "C"},
+			},
+			expected: "A  B  C",
+		},
+		{
+			name: "Column with gap",
+			opts: FlexOptions{
+				Direction: Column,
+				Width:     1,
+				Height:    5,
+				Gap:       1,
+				Align:     AlignStart,
+			},
+			items: []FlexItem{
+				{View: "A", FixedSize: 1},
+				{View: "B", FixedSize: 1},
+				{View: "C", FixedSize: 1},
+			},
+			expected: "A\n \nB\n \nC",
+		},
+		{
+			name: "Row with gap and justify space between",
+			opts: FlexOptions{
+				Direction: Row,
+				Width:     15,
+				Height:    1,
+				Gap:       1,
+				Justify:   JustifySpaceBetween,
+			},
+			items: []FlexItem{
+				{View: "A"},
+				{View: "B"},
+				{View: "C"},
+			},
+			expected: "A      B      C",
+		},
+		{
+			name: "No gap specified",
+			opts: FlexOptions{
+				Direction: Row,
+				Width:     10,
+				Height:    1,
+			},
+			items: []FlexItem{
+				{View: "A"},
+				{View: "B"},
+				{View: "C"},
+			},
+			expected: "ABC",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := Render(tt.opts, tt.items...)
+			// Trim any trailing spaces for comparison
+			result = strings.TrimRight(result, " ")
+			expected := strings.TrimRight(tt.expected, " ")
+
+			if result != expected {
+				t.Errorf("Render() = %q, want %q", result, expected)
+			}
+		})
+	}
+}